asid,bes.k2.struktur(bahagian 2)

8/17/2019 Asid,Bes.K2.Struktur(Bahagian 2)

1/4

4 (a) 8g of solid sodium hydroxide, NaOH, is dissolved is distilled water to produce a solution of 1 cm !"

#he NaOH solution produced has the concentration of 8 g dm$! and molarity of "% mol dm$!" 8 g pepejal natrium hidroksida, NaOH, dilarutkan dalam air suling untuk menghasilkan larutan

yang mempunyai isi padu 1000 cm! "Larutan NaOH yang terhasil itu mempunyai kepekatan 8 g dm$! dan kemolaran "% mol dm$!"

(i) &tate the meaning of the concentration for the solution produced"Nyatakan maksud kepekatan bagi larutan yang terhasil.

''''''''''''''''''''''''''''''''''''''''''"" [1 mark]/[lmarkah]

(ii) &tate the meaning of the molarity for the solution produced"Nyatakan maksud emolaran bagi larutan yang terhasil.

'''''''''''''''''''''''''''''''''''''''''""" 1 mark]/[l

markah] (ii) rite the formula that represents the relationship *etween the num*er of mole (n),molarity (+)

andvolume () for the solution"

Tulis rumus yang mewakili hubungan antara ilangan mol !n", kemolaran !#" dan isi padu !$"

bagi larutan itu.

'''''''''''''''''''''''''''''''''''''''''' [1 mark]/[l markah]

(iv) &u*stitute the actual values of the num*er of mole, molarity and volume of the NaOH solution into the formula in 4(a)(iii)"

-.elative molecular mass of NaOH / 40

%antikan nilai&nilai sebenar bagi bilangan mol, kemolaran dan isi padu larutan NaOH itu kedalam rumus 4(a)(iii)"

['isim molekul relati( bagi NaOH / 4)

''''''''''''''''''''''''''''''''''''''''''"" [1 mark]/[1 markah] (ii) fter all the NaOH "2olution is poured into the volumetric flas, the *eaer and the filter funnel must *e3 rinsed several times with distilled water" fter each rinse, all3of this water is transferred into the volumetric flas"" ive one reason for doing

this" )elepas semua larutan NaOH dituangkan ke dalam kelalang *olumetri, bikar dan +orong turas

perlu dibias beberapa kali dengan air suling. )elepas setiap ilasan, semua air ilasan itu dipindahkan masuk ke dalam kelalang *olumetri.eri satu sebab mengapa ini perlu dilakukan.

''''''''''''''''''''''''''''''''''''''''''"

''''''''''''''''''''''''''''''''''''''''''" [1 mark] [1 markah]

(iii) hat step should *e taen to ensure that the meniscus level of the standard solution is exactly inline with the graduation mar on the volumetric flas5

-pakah langkah yang perlu dilakukan untuk memastikan aras meniskus larutan piawai, segarisdengan tepat dengan tanda senggatan pada kelalang *olumetri


2/4

''''''''''''''''''''''''''''''''''''''''""""""""" [1 mark]/[1 markah]

(iv) volumetric flas is more suita*le to *e used in the preparation of the standard solution rather than a*eaer"hy5

elalang uolumetri lebih sesuai digunakan untuk menyediakan larutan piawai berbanding denganbikar.#engapa

''''''''''''''''''''''''''''''''''''''''''' [1 mark][l markah] (v)hy is the volumetric flas stoppered after the standard solution is prepared 5 #engapa kelalang *olumetri+ ditutup setelah larutan piawai disediakan

'''''''''''''''''''''''''''''''''''''''''''" [1 mark][l markah]

(*) 6iagram 4"1 shows the preparation of the standard solution of NaOH, "% mol dm $!"ajah .1 menunjukkan penyediaan larutan piawai NaOH, "% mol dm$!"


3/4

(i) hat are the two parameters that should *e measured accurately to prepare the standard

solution of NaOH5

-pakah dua parameter yang perlu disukat dengan tepat untuk menyediakan larutan piawai NaOH

itu

7arameter 9

2arameter 34 ''''''''''''''''''''''''''''''''''''''""

7arameter 92arameter 334''''''''''''''''''''''''''''''''''''''""

-% marks] -%markah]


4/4

asid,bes.k2.struktur(bahagian 2)

Documents